1. Field
The present specification relates to a display apparatus configured using various thin display devices such as an organic EL (Organic Electro-Luminescence) display panel, an LCD (Liquid Crystal Display) panel, and an electronic paper.
2. Description of the Related Art
Thin display devices such as an organic EL display panel and an LCD panel are used in various display apparatuses. In recent years, extremely thin display devices such as a so-called electronic paper capable of electrically controlling display have been put to practical use. The electronic paper has high visibility and being thin and flexible with low power consumption, but has slow response speed during display change.
That is, the electronic paper has the following advantages: (1) the power consumption is not necessary for display, or an extremely small amount of power is sufficient therefor, and thus the power consumption at the time of rewriting is also extremely low; and (2) its viewing angle is wide and its visibility is excellent even under direct sunlight, and since a plastic film or the like which is formed to be thin like paper is used as a display base, it is possible to perform display without lowering display quality even when bending the electronic paper. However, in the case of an electrophoretic electronic paper, there are disadvantages in that the response speed during display change is slow and it is not suitable for moving picture display.
Besides the utilization form in which the electronic paper having such characteristics is used in, for example, an electronic book reader apparatus that displays so-called electronic book data transferred as digital data, various new utilization forms are conceivable. For example, Japanese Unexamined Patent Application Publication No. 2007-334237 to be described later discloses a display system in which moving picture contents such as movies are displayed on a normal monitor apparatus such as an LCD display apparatus in the same manner used in the past, and textual information, management information, and the like added to the moving picture contents are displayed on an electronic paper.
In Japanese Unexamined Patent Application Publication No. 2007-334237, the monitor apparatus, which displays moving picture contents, and the electronic paper apparatus, which displays textual information associated with the corresponding moving picture contents, are configured to be separated. With such a configuration, in order to display the textual information and the like, reproduction of the moving picture contents is stopped, or the moving picture and the textual information are displayed in a superimposed manner. In such a manner, it is possible to avoid inconvenience such as difficulty viewing the display information.
In recent years, various kinds of so-called mobile apparatuses such as mobile phone terminals, personal information terminals called PDAs (Personal Digital Assistants), and personal laptop computers have come into widespread use. Since the mobile apparatus is used while being carried, a battery is used as a drive power source. For this reason, it is preferable that power consumption in the mobile apparatus should be as low as possible. The reason is that discharge of battery should be avoided when possible.
For this reason, in the mobile apparatuses, in the same manner as Japanese Unexamined Patent Application Publication No. 2007-334237 mentioned above, it can be considered that there are provided a display device having a high response speed and relatively high power consumption and a display device having a low response speed and extremely low power consumption. In addition, by changing the display devices used in accordance with the display information, it is possible to achieve lower power consumption than the mobile apparatuses of the related art equipped with only a display device having a high response speed and relatively high power consumption.
As it is, in the mobile apparatuses, as information to be displayed is diversified, not only the size of display screen increases, but also there is a demand for a decrease in size and weight, and thus it is difficult to provide a plurality of display devices each of which has a large display screen. The reason is that providing the plurality of display devices each of which has a large display screen is linked with the increase in size of the mobile apparatus.
In consideration of the above, without increasing the size of the casing itself and decreasing the size of the display screen, it is desirable to provide a display apparatus including a plurality of display devices each of which has a relatively large screen.